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Ribbon Sendust Heads

Sendust material can now be produced in ribbon forms which possesses all of the properties necessary for local tape heads for recording and playback, including: 1) High malleability, permitting easy machining, 2) high initial permeability, over 32,000, permitting high sensitivity for playback heads, 3) low coercivity, less than 0.2 Oersteds, permitting low magnetizing noise for record and playback heads, 4) high saturation flux density, over 9,000 gauss, permitting easy recording on high energy metal tapes, 5) thickness as small as 20 micrometers permitting high frequency performance comparable to the best ferrites to over 20 kHz, and 6) high wear-resistance, less than 2 micrometers per 1000 hours. Some details of the manufacturing process will be discussed along with the measured head performance data.